Apparatus for operating electric luminous tubes



J. FoboR July 13; 1937.

APPARATUS FOR OPERATING ELECTRIC LUMINOUS TUBES 5 Sheets-Sheet l Filed July 25, 1934 INVENTOR July 13, 1937.

J. FODOR APPARATUS FOR OPERATING ELECTRIC LUMINOUS TUBES 3 Sheets-Sheet 2 Filed July 25, 1934 INVENTOR July 13, 1937. J, FQDOR 2,086,668

RATUS FOR OPERATING ELECTRIC LUMINOUS TUBES 5 Sheets-Sheet 5 APPA Filed July 25, 1934 //v VENTOR Patented July 13, 1931 UNITED STATES PATENT OFFICE APPARATUS FOR OPERATING ELECTBIO LUMINOUS TUBES Application July 25, 1934, Serial No. 736,928 In Great Britain September 23, 1933 20 Claims.

This invention relates to apparatus for energizing one or more similar and/or different electric tubes with high frequency current to produce K a continuous or a varying lighting effect. Y It is an object of this invention to provide means whereby the harmful effect which capacitive, inductive and resistive variation of the tube circuits have upon the high frequency transformation is eliminated. A further object is to permit the apparatus to operate several and different tubes at the same time. Another object of the invention is to avoid "disturbing reactions in the high frequency transformer of the system and a still'further object is to provide means whereby the tensions supplied by the apparatus at the ends of the tubes can be divided, at will, to suit operating requirements.

Apparatus according, to the invention is characterized by circuits having connected with them means adapted to eliminate the efiects of variations produced in the tube circuit or circuits by externaljniluences so as to permit tuned transformation to be maintained. According to the 5 invention the. variations in question are outweighed or rendered inefiective by means of suitable capacities, self-inductances or resistances connected in parallel or in series with the secondary circuit of the high frequency transformer, or by making the secondary and the tube circuits,

respectively aperiodic.

. In order to operate several and different tubes 'off the same apparatus at the same time, a high frequency transformer is used, which has several secondary circuits. Alternatively or additionally, the secondary circuit or any or each of such circuits, when there is more than one, is designed as a capacitive, inductive or resistive potential divider, thus providing for the tapping ofi'of the 4 different tensions required by the different tubes.-

-Inany case the apparatus includes suitable arrangements for. preventing undesirable effects due to variations in the tube circuits as mentioned hereinbefore.

'45 i The secondary V transformer, when the higher tensions required bythe tubes are generated, sets up a disturbing reaction upon the primary side of the said tr'ansformer and, consequently, upon the generator 50 itself but according to the present invention this disturbance is avoided by dividing the secondary side into several windings of which one only is coupled to theprimary side.

Owing to the asymmetry of the high frequency '65} transformer or the tube circuits, the tubes receive.

side a: the high frequency (Cl. 176 -124) J diiferent tensions at their ends. In order to avoid this usually uneconomical method of feeding, the high frequency transformer is earthed in its symmetry-centre and/or coupling condensers are introduced into each of the leads of the tube 5 circuits. Both these methods may, however, be

used in modified form tosupply the ends of the tubes with different, optional, or periodically varying tensions.

This invention will now more particularly be described with reference to the accompanying drawings, in which:

Fig. 1- is a general circuit diagram illustrating a valve generator operating an electric luminous tube, the said tubeiitself and the high frequency transformer connecting these latter.

Fig. 2 illustrates the elimination of the. effects of capacitive variations of the leads and the tubes by means of a parallel condenser.

Fig. 3 illustrates thfiielimination of the effects of capacitive variations of the leads and the tubes by means of a series condenser.

Fig. 4 illustrates the elimination of the effects of capacitive variations of the leads and the tubes by both parallel and series condensers.

Fig. 5 illustrates how the circuit formed by the high frequency transformer, the leads and the tubes is made aperiodic.

Fig. 6 illustrates an arrangement in which, although the' secondary circuit of the high fre-- quency transformer is periodic the circuit formed by the leads and tubesis aperiodic.

Fig. 7 illustrates a high frequency transformer having several secondary windings each feeding a corresponding tube circuit.

Fig. 8 illustrates a high frequency transformer with several tappings for the different tube circuits.

Fig. 9 is a variation of Fig. 8.

Fig. 10 illustrates a high frequency transformer in connection with a potential divider.

Fig. 11 illustrates a high frequency transformer in connection with a capacitive potential divider.

Fig. 12 illustrates how to avoid the disturbing reaction of the secondary side upon the primary side of the high frequency transformer by dividing the secondary winding into several parts in such a manner that a loose coupling between the primary and secondary windings is obtained.

' Fig. 13 illustrates a method of obtaining tension symmetry in a tube circuit.

Fig. 14 illustrates a capacitive method of compensating a tube circuittwith a view of obtaining tension symmetry. 5

Although in the drawings the diagrammatic representations of electric luminous tubes indicate tubes provided with internal electrodes, it is to be understood that the present invention is equally applicable to apparatus and circuits for the operation of so-called electrodeless luminous tubes, or such with external electrodes.

Fig. 1 of the drawings illustrates by way of example, a valve I arranged for operation as a high frequency generator. duced by this valve are transferred to the tubes 5 by a high frequency transformer 2. This cou pling device, on its primary side 3, is'matched according to well known technical rules to the valve generator I and is, in the present case, identical with the oscillator windings of the oscillatory circuit for the valve generator although separate oscillator windings may be provided if desired. The secondary winding 4 of the transformer 2 is so dimensioned as, on the one hand, to produce the higher tension required to strike and operate the tubes 5 and, on the other hand, to satisfy techanical requirements as regards cou pling with a view to matching the circuit elements to obtain maximum efficiency. For this purpose, a frequency may be chosen for the generator I identical with the natural frequency of the oscillatory circuit or circuits 6 formed by the secondary side 4 of the coupling transformer 2 and the tube or tubes 5 connected thereto, or an harmonic relationship may be established between the generator frequency and the tube circuit frequency, the object, in either case, being to obtain tuned transformation.

It may easily happen that, owing to weather conditions or other influences, or if the tubes be exchanged or interchanged, variations occur in the electrical constants (self-inductance, capacity, resistance, etc.) of the tube or tubes 5 connected to the high frequency transformer 2' or in those of its leads which are indicated by the dotted lines in Fig. 1. Such variations, by altering the natural frequency of the oscillatory circuit 6, formed by the tubes, their leads and the high frequency transformer winding, would in i order to maintain tuned transformation, necespendent oscillatory circuit I0. This capacity "I is.

so large that, by comparison with it, the capacitive variations in the leads (as indicated in dotted lines at 89 and those in the tubes (as indicated in dotted lines at 9) become negligible. Thus these latter capacitive variations will, for all practical purposes, only influence the natural frequency of the oscillatory circuit I0 to'a negligible extent, for which reason said circuit ID will at all times continue to be fed with frequencies corresponding to its natural frequency, although the generator frequency is not varied.

In the circuit arrangement shown in Fig. 3 a capacity I I is connected in series with the secondary winding 4 of the high frequency transformer 2, the value of such capacity II being sr'naiier than the capacitive variations indicated by 8 and 9. This arrangement gives, in effect, substantially the same result as that shown in Fig. 2,

The oscillations pro- Similaradjustments would be necessary if the natural frequency 'of the oscillatory circuit 6 remaining practically constant, notwithstanding capacitive variations in the tubes or in their leads. By suitably choosing the value of the series capacity II the natural wavelength of the circuit formed by the secondary side of the transformer 2, the leads and the tubes can be so shortened as to permit of operation of the tubes by short waves.

The common principle of the methods illustrated by Figs. 2 and 3 consists in this; that, in order to maintain the natural frequency of an oscillatory tube-feeding circuit practically constant, in spite of certain capacitive variations, such additional capacities are coupled (either in series or in parallel) to this oscillatory circuit, in accordance with well known rules of the technics. of high frequency, that, compared with the value of these latter, the said capacitive variations become negligible. On the same principle, the addition, in series or in parallel, of suitable self-inductances and resistances will result in eliminating'the effects of inductive or resistive variations occurring in the tubes or in their leads. These methods can, in practice, be applied in combination in such a way as to render ineffective capacitive, inductive and resistive variations which themselves occur in combination.

Fig. 4 represents a variation of the methods shown by Figs. 2 and 3. The secondary side 4 of the high frequency transformer 2 is, by the addition of a capacity I, designed as an independent oscillatory circuit Ill. The capacities i2 and I3 which connect the oscillatory circuits 6 and Ill, are so small that the capacitive variations indicated by 8 and 9 will not influence the natural frequency of the oscillatory circuit IIi. By the suitable coupling of suitable self-inductances this method can also be used to outweigh inductive variations.

According to Fig. 5 the oscillatory circuit 8, formed by the secondary side 4 of the high fre- V quency transformer 2 and the leads and tube 5,

is for instance, by the introduction of a resistance I4 made aperiodic. In this case the aperiodicity is responsible for elimination of undesired effects due to capacitive, self-inductive and resistive variations occurring in the leads and in the tubes,

Fig. 6 shows a variation on the arrangement shown in Fig. 5. In this case, although the secondary side 4 of the high frequency transformer 2 is, by the addition of the capacity I, made part of an independent oscillatory circuit It), the circuit 8, formed by the leads and tubes, is made aperiodic, for instance, ohmically by the introduction of the resistances I5 and I6.

In order to operate several and, if necessary. different tubes off one and the same apparatus the secondary side of the high frequency transformer can be designed in any of the ways shown in Figs. 7 to II.

According to Fig. 7 the high frequency transformer 2, though having only one primary wind- -ing, is-provided with a plurality of secondary vider.

or some of the secondary circuits may be de- "tuned or, again, those are to supply a smaller tension may,

to the tension required, be tuned to one of the secondary windings which according harmonics of the primary frequency.

According to Fig. 8 the secondary side-4 of the high frequency .transformer 2 is constructed as a potential divider. has/for this purpose, a suitable number of tappings, 4 4 4, which permit not only of the suitable choice. of the tensions required by the different tubes or groups of tubes, but also of the right selection of the values of the self-inductances influencing the natural frequency of the secondary circuits 6, 6 6

Fig. 9, which illustrates a variation of Fig. 8, shows how to apply one of the methods illustrated by Figs. 2 to 6, the one selected, by way of example, being that shown in Fig. 2 The large shunt capacities, l 1*, 1, on the one hand, eliminate the effects of capacitive variations occurring in the circuits 6*, 6 6, and, on the other hand, permit the circuits connected to the various sections of transformer secondary winding to be tuned to a common frequency.

Fig. 10 represents'the case of an ohmic potential divider. The secondary side 4 of the high frequency transformer 2' is here shunted by a resistance H which, in its turn, is tapped off according to the tensions required to operate the different tubes or groups of tubes. Fig. ll rep-- resents the case of a capacitive potential di- The secondary coil 4 of the high frequency transformer 2, having been made part of an oscillatory circuit Ill by the inclusion. of

the capacity I, feeds a system of capacities, I8 I8 l8, connected in series. The values of these latter capacities can be chosen in accordance with the tensions required for the tubes 5 5 59.

In order'to avoid disturbing reaction of the secondary side, 4 of the high frequency transformer. 2 on the primary side 3 thereof and thus to avoid the generation of distorted, for instance, double waves, according to Fig. 12 the secondary winding 4 is divided into several parts, such as; 4 and 4 of which only one is coupled to the primary winding 3.

For the purpose of energizing the tubes at the highest grade of efficiency the secondary winding 01' windings of the high frequency transformer may, ,with advantage be furnished with means for correcting asymmetric distribution of tensioncaused by the tubes, their leads or their direct coupling elements or by any other influence in the tube feeding circuit or circuits. The object of this precaution is to ensure that the tubes receive equal tensions at both ends even though such tensions, may perhaps, differ in phase.

Fig. 13 illustrates one method of making the desired correction. In this particular case the secondary side "4 of the high frequency transformer! is earthed at its tension symmetry centre N, which is'to be distinguished from its geometric mid-point. Another method is illustrated by Fig. 14. Here the secondary side 4 of the high frequency transformer 2 feeds the tube 5 through required to sup The secondary winding 3 the adjustable capacities 20, 2|, in which case the ends of the tubes 5 will receive higher or lower tensions according to justable capacities.

The methods as illustrated by Figs. 13 and 14 can ofcourse also be applied to the purpose of imparting or group of tubes, than to the other, or to the a higher tension ,to one end of a tube;

the value of the said adpurpose of obtaining periodic variations of tehsion at the ends 'of the tubes. In this latter case the earthing connection as indicated in Fig. 13

is not established permanently at the tension symmetry centre I9 but is moved by some suitable means periodically along the winding or, according to Fig. 14 the values of the capacities 20, 2! are by some suitable means varied period'- ically.

I claim:

1. Apparatus for energizingan electric luminous tube comprising in combination a source of high frequency current, a transformer connected to said source of current, an electric luminous tube connected to the secondary winding of said transformer, and means associated with the secondary circuit to cause it-to be made aperiodic.

2.'Apparatus for energizing an electric luminous tube comprising in combination a source of high. frequency current, a transformer connected to said source of current, an electric luminous tube connected to the secondary side of said transformer, tuning means associated with said secondary side, and means associated with the tube circuit coupled with the secondary oscillatory circuit for causing said tube circuit to be made aperiodic.

3. Apparatus for energizing electric luminous tubes comprising in combination a source of-high frequency current, a transformer having a primary winding which is connected to said source of current, a plurality of secondary windings on said transformer, and an electric luminous discharge tube connected to each of said secondary windings.

4. Apparatus for energizing electric luminous tubes comprising in combination a source of high frequency current, a transformer having a primaryewinding which is connected to said source 1 of current, a plurality of secondary windings on said transformer, an electric'luminous tube connected'to each of said secondary windings, said secondary windings having different numbers of turns so that the requisite voltages are applied to the corresponding tubes, and means associated with each of said secondary windings for tuning said secondary circuits to multiples of the frequency of the source of current.

.5. Apparatus for energizing several and different electric luminous tubes comprising in combination a source of high frequency current, a transformer connected to saidsource of current, a potential divider associated with the secondary winding of said transformer including a plurality of tappingsfroni which different voltages and if required different frequencies can be tapped,

and a' plurality of electric luminous tubes connected to corresponding points of the potential divider. a

6. Apparatus for energizing an. electric luminous tube comprising in combinationa source of high frequency current, a transformer having a primary. winding connected to said source of current, an electric luminous tube connected to the secondary side of said transformer, said secondary side being divided into several parts only one of which is coupled to the primary winding.

'7. Electric luminous discharge apparatus comprising, in combination, a plurality of electric luminous discharge devices, a source of high frequency current; a high frequency transformer, said transformer having a primary side connected to be supplied from said source and a secondary side comprising a plurality 'of secondary circuits, each of said secondary circuits being connected to supply an individual one of said electric luminous discharge devices with high frequency electrical tension, and means including electrical impedance elements in each of said secondary circuits for adjusting the natural frequency of said circuit to supply the corresponding electric luminous discharge device with high frequency electrical tension which is suited to the individual requirements of said electric luminous discharge device.

8. Electric luminous discharge apparatus comprising, in combination, a plurality of electric luminous discharge devices having different electrical characteristics, a source of high frequency current, a high frequency transformer, said transformer having-a primary side connected to be supplied from said source and a secondary side comprising a plurality of secondary circuits, each of said secondary circuits being connected to supply an individual one of said electric luminous discharge devices with high frequency electrical tension, and means including electrical impedance elements in each of said secondary circuits for adiusting the natural frequency of said circuit to supply the corresponding electric luminous discharge device with high frequency electrical tension which is suited to the individual requirements of said electric luminous discharge device.

9. Electric luminous discharge apparatus comprising, in combination, a plurality of electric luminous discharge devices, a source of high frequency current, a high frequency transformer, said transformer having a primary winding connected to be supplied from said source and a plurality of separate secondary windings and associated secondary circuits, each of said secondary circuits and associated secondary transformer windings being connected to supply an individual one of said electric luminous discharge devices with high frequency electrical tension, and means including electrical impedance elements in each of said secondary circuits for adjusting the natural frequency of said circuit to supply the corresponding electric luminous discharge device with high frequency electrical tension which is suited to the individual requirements of said electric luminous discharge device.

10. Electric comprising, in combination, a plurality of electric luminous discharge devices, a source of high frequency current, a high frequency transformer, said transformer having a primary winding connected to be supplied from said source and a plurality of separate secondary windings and associated secondary circuits, said secondary windings having diflerent numbers of turns in accordance with the different tensions required in the associated secondary circuits and each of said secondary circuits being connected to supply an individual one of said electric luminous discharge devices with high frequency electrical tension, and means including electrical impedance elements in each of said secondary circuits for adjusting the natural frequency of said circuit to supply the corresponding electric luminous discharge device with high frequency elecluminous discharge apparatusaoeaees trical tension which is suited to the individual requirements of said electric luminous discharge device.

11. Electric luminous discharge apparatus comprising, in combination, a plurality of electric luminous discharge devices, a source of high frequency current, a high frequency transformer, said transformer having a primary side connected to be supplied from said source and a secondary side comprising a plurality of secondary circuits, each of said secondary circuits being tuned to the same natural frequency and being connected to supply an individual one of said electric luminous discharge devices with high frequency electrical tension, and means including electrical impedance elements in each of said secondary circuits for adjusting the natural frequency of said circuit to supply the corresponding electric luminous discharge device with high frequency electrical tension which is suited to the individual requirements of said electric luminous discharge device.

12. Electric luminous discharge apparatus comprising, in combination, a plurality of electric luminous discharge devices, a source of high frequency current, a high frequency transformer, said transformer having a primary side connected to be supplied from said source and a secondary side comprising a plurality of secondary circuits, at least one of said secondary circuits being tuned to a. harmonic of the primary frequency in accordance with the tension requirements of said secondary circuit and each of said secondary circuits being connected to supply an individual one of said'electric luminous discharge devices with high frequency electrical tension, and means including electrical impedance elements in each of said secondary circuits for adjusting the natural frequency of each of. said circuits to supply the corresponding electric luminous discharge device with high frequency electrical tension which is suited to the individual requirements of said electric luminous discharge device.

13. Electric luminous discharge apparatus comprising, in combination, a plurality of electric luminous discharge devices, a source of high frequency current, a high frequency transformer, said transformer having a primary side connected to be supplied from said source and a secondary side comprising a plurality of secondary circuits, at least two of said secondary circuits being tuned to different frequencies in accordance with the tension requirements of said secondary circuits, and each of said secondary circuits being connected to supply an individual one of said electric luminous discharge devices with high frequency electrical tension, and means including electrical impedance elements in each of said secondary circuits for adjusting the natural frequency of said circuit to supply the corresponding electric luminous discharge device with high frequency electrical tension which is suited to the individual requirement of said electric luminous discharge device.

14. Electric luminous discharge apparatus, comprising in combination, a plurality of electric luminous discharge devices, a. source of high frequency current, a high frequency transformer, said transformer having a primary side connected to be supplied from said source and a secondary side connected to said electric luminous discharge devices, and a potential divider associated with said secondary side of said transformer to provide a plurality of secondary circuits each of whichis connected to an individual one of said electric luminous discharge devices, whereby different tensions are tapped off on said secondary side of said transformer to energize said electric luminous discharge'devicesin accordance with the individual requirements thereof.

15. Electric luminous discharge apparatus,

comprising, in combination, a plurality of electric luminous discharge devices, a source of high frequency current, a high frequency transformer. said transformer having a primary side connected to be supplied from said source and a secondary side connected to said electric luminous discharge devices, and an inductive potential divider associated with said secondary side of said transformer to provide a plurality of secondary circuits each of which is connected to an individual one of said electric luminous discharge devices, whereby different tensions are tapped off on said secondary side of said transformer to energize said electric luminous discharge devicesin accordance with the individual requirements thereof.

16. Electric luminous discharge apparatus, comprising, in combination, a plurality of .electric luminous discharge devices, asource of high frequency current, a highfrequency transformer,

said transformer having a primary side connected to be supplied from said source and a secondary side connected to said electric luminous discharge devices, and anohmic potential divider associated with said secondary side of said trans;

former to provide a plurality ofsecondary circuits each of which is connected to an individual one of said electric luminousdischarge devices, 2

whereby different tensionstappedofi on said secondary side of said transformer to energize said electric luminous discharge devices in accordance with the individual requirements thereof. I

17. Electric. luminous discharge apparatus. comprising, in combinatioma plurality of electrio luminous discharge devices, a source of high frequency current, a high frequency transformer,

said transformer having a primary side connected to be supplied from said source and a secondary'side connected to said electric luminous discharge devices, and a. capacitive potential divider associated with said secondary side of said transformer to provide a plurality of secondary circuits each of which is connected to the individual one of said electric luminous discharge I devices, whereby different tensions are tapped off on said secondary side of said transformer to energize said electric luminous discharge devices in accordance with the individual requirements thereof.

18. Electric luminous discharge apparatus comprising in combination a plurality of electric luminous discharge devices, a source of high frequency current, a high frequency transformer, said transformer having a primary side connected to'be supplied from said source and a secondary side comprising a plurality of secondary circuits, each of said secondary circuits being connected to supply an individual one of said electric luminous discharge devices with high frequency electrical tension, at least one of said electric luminous discharge devices being loosely coupled to its associated secondary circuit by a small capacity, and means including electrical impedance elements in each of said secondary circuits for adjusting the naturaLfrequency of the corresponding circuit to supply the corresponding electric luminous discharge device with high frequency electrical tension which is suited to the individual requirement of said electric luminous discharge device. s

19; Means'for energizing a plurality of electric luminous discharge devices comprising, in

combination, a source of high frequency current,

having a primary side connected to be supplied fromsaid source and a secondary side comprising a plurality of secondary circuits, each of said secondary circuits being connected to supply an individual electric luminous discharge device w with high. frequency electrical tension, at least one of said secondarycircuits comprising means for rendering said secondary circuit aperiodic. 20..Electric- .lumin'ous discharge apparatus comprising, in combination, a plurality of electric luminous discharge devices, a source of high frequency current, a high frequency transformer, said transformer having a primary side connected to be supplied from said source anda secondary side comprising a plurality of secondary circuits each of said secondary circuits being connected to supply an individual one of said electric luminous discharge devices with high frequency electrical tension, at least one of said secondary circuits comprising means for rendering said secondary circuit aperiodic.

JOBIPH IODOR. 

